1. Field of the Invention
The present invention relates to a magnetic ink character reading apparatus for reading a text string generated from a sequence of magnetic ink characters on a check or other medium. The present invention also relates to a magnetic ink character reading method for reading magnetic ink characters printed on a check or other medium using a magnetic ink character reading apparatus, and to a program for achieving this magnetic ink character reading method. This invention further relates to a POS terminal having a magnetic ink character reading apparatus.
2. Description of the Related Art
Business checks and personal checks (collectively referred to below as simply checks) are commonly used to make payment in a variety of circumstances, for example, in business-to-business transactions as well as for retail purchases in stores and restaurants. Checks are particularly common in the United States and Europe. A bank code, account number, and other information are printed with magnetic ink characters at a specific position (typically a line along the bottom) on each check. When a check is used for payment in a retail store, for example, the user (checking account holder) writes the name of the payee, the check amount in both numbers and words, and then signs the check before giving the check to the store as payment for a purchase. The store can then read the bank code and account number printed in magnetic ink characters, send the read data to the bank or other financial institution or clearing house for verification, and thus know if the presented check is valid or not. If the check is valid, the store prints an endorsement on the back of the check and thus accepts the check as payment.
The bank code and account number information printed in magnetic ink characters are required to settle check payment transactions and must therefore be correctly read. If the magnetic ink characters are incorrectly recognized, transaction processing will proceed based on incorrect data, potentially resulting in major post-processing problems such as the wrong account, that is, an account other than the account on which the check is actually drawn, being debited for payment. Correctly reading the magnetic ink characters is therefore essential when processing check transactions. The character recognition technologies used in magnetic ink character recognition (MICR) readers have therefore been tweaked to improve the recognition rate and reduce character recognition errors.
Japanese Unexamined Patent Appl. Pub. S49-49545 and Japanese Unexamined Patent Appl. Pub. H7-182448 provide technologies for improving the recognition rate by also using an optical character recognition (OCR) reader to optically read characters that could not be read magnetically.
Considering the potential for erroneously recognizing the content even though the characters can be read, Japanese Unexamined Patent Appl. Pub. 2000-259764 provides technology for reducing the false recognition rate by comparing the recognition output of the MICR reader and the recognition output of the OCR reader and accepting as correct only those results that are the same.
In order to reliably read the area where the magnetic ink characters are printed, however, an area larger than the actual area of the magnetic ink characters must be read because of variations in the printing position of the magnetic ink characters, variations in check dimensions, and variations in the dimensions of the MICR reader, for example. When the area read for character recognition is thus increased, however, the signature line where the check-holder signature is written and the background pattern, for example, may encroach on the area that is read, and the OCR reader may mistakenly read the signature or background pattern around the magnetic ink characters. The signature, background pattern, and other elements that are not magnetic ink characters but may be mistakenly recognized by the OCR reader are referred to below as “noise characters.”
Because these noise characters are not magnetic ink characters, the likelihood of noise characters being erroneously recognized by the MICR reader is extremely low. However, even if the MICR reader correctly reads the magnetic ink characters without being affected by these noise characters, the OCR reader could still read noise characters, resulting in recognition errors. Thus, because there is a danger of recognition errors if the reading results of the MICR reader and OCR reader differ, differences in the reading results are preferably handled as unreadable errors. Considering this possibility of content recognition errors even though the data is read correctly, using an OCR reader in addition to a MICR reader can thus conversely lower the recognition rate.